Hydroxyapatite/tannic acid composite coating formation based on Ti modified by TiO2 nanotubes.

Oxidative stress induced by reactive oxygen species (ROS) overproduction and accumulation would hinder the osseointegration process at the bone-implant interface, leading to a higher rate of implant failure. To endow titanium (Ti) implants with antioxidant activity, we developed a coating approach mediated by tannic acid (TA)-Ca2+ coordination complexation. A hydroxyapatite (HA)/TA composite coating was prepared, based on Ti substrates modified by anodized and annealed titanium dioxide (TiO2) nanotube arrays. The results reveal that highly ordered TiO2 nanotubes with a diameter of 142.23 ±â€¯14.52 nm and a length of 374.17 ±â€¯42.47 nm were fabricated on the Ti substrate and the XRD pattern shows the TiO2 anatase phase after annealing at 450 ℃. TA-Ca complexes were formed on the surface of TiO2 nanotubes by immersing the constructs into the mixed solution of TA and CaCl2, where they are served as calcium sites for the HA growth by later phosphorylation. The HA nanoparticles present needle-shape with the diameter of 18 ∼ 20 nm. The total antioxidant capacity assay was employed to confirm the antioxidant effect of the HA/TA composite coating. The results indicate that it has a persistent and strong antioxidative activity. In vitro cytological test results show that HA/TA coating exhibits good cytocompatibility for osteoblasts proliferation and adhesion.

Percutaneous treatment with drug-eluting stent vs bypass surgery in patients suffering from chronic stable angina with multivessel disease involving significant proximal stenosis in left anterior descending artery.

BACKGROUND: The aim of the present study was to compare the effects of drug-eluting stents (DES) and coronary artery bypass grafting (CABG) in patients suffering from chronic stable angina with multivessel disease, involving significant proximal stenosis in the left anterior descending artery (LAD). METHODS AND RESULTS: All consecutive patients suffering from chronic stable angina with multivessel disease involving significant proximal LAD stenosis underwent DES implantation (n=600) or CABG (n=709) at our institution. At 2 years, the unadjusted mortality was significantly lower in the DES group than in the CABG group (2.2% vs 5.2%, P=0.004), but the adjusted risk of death was similar (odds ratio (OR) 0.74, 95%CI 0.28-1.97, P=0.555). Furthermore, both the adjusted rate of nonfatal myocardial infarction and cerebrovascular events was also comparable. However, the unadjusted and adjusted risk of major adverse cardiac cerebrovascular events in the DES was significantly higher than in the CABG (13.3% vs 9.6%, OR 2.71, 95%CI 1.56-4.74, P<0.001), which is probably attributed to the higher subsequent revascularization rate after DES implantation. CONCLUSIONS: DES showed comparable long-term mortality for the treatment of multivessel disease involving significant proximal stenosis in LAD in comparison with CABG.

Prolonged dual antiplatelet therapy improves clinical outcomes in high-risk patients implanted with sirolimus-eluting stents.

BACKGROUND: Although a science advisory recommending 12 months of dual antiplatelet therapy after drug-eluting stents implantation was published recently, the optimal duration of dual antiplatelet therapy has not yet been precisely determined. HYPOTHESIS: Prolonged dual antiplatelet therapy can improve clinical outcomes in high-risk patients implanted with sirolimus-eluting stents. METHODS: The patients implanted with sirolimus-eluting stents were assigned into standard clopidogrel therapy group (clopidogrel 75 mg/d for 12 mo) and prolonged clopidogrel therapy group (clopidogrel 75 mg/d for 18 mo). Long-term aspirin (100 mg/d) therapy was adopted in both groups. The primary endpoint was very late stent thrombosis. RESULTS: After 12 months, 24 patients were excluded because of major adverse cardiovascular events (MACEs). Three hundred and thirty six patients surviving without MACEs were further followed up for 6 months. Between 12 and 18 months, in 160 patients with standard clopidogrel therapy, 5.6% had very late stent thrombosis. In contrast, in 176 patients with prolonged clopidogrel therapy, 1.1% had very late stent thrombosis (p<0.01, versus standard clopidogrel therapy group). CONCLUSIONS: Prolonged dual antiplatelet therapy may be beneficial to prevent very late stent thrombosis after sirolimus-eluting stents implantation in high-risk patients.

Impact of metabolic syndrome on clinical outcomes after drug-eluting stent implantation in patients with coronary artery disease.

Metabolic syndrome (MetS) is regarded as a risk factor for coronary artery disease (CAD). However, the influence of MetS on morbidity and mortality after drug-eluting stent (DES) implantation in Chinese patients with CAD remains unknown. We evaluated the impact of MetS on the clinical outcome of 1224 patients following DES implantation. After a mean follow-up of 35.4 months, patients with MetS had a significantly higher incidence of all-cause death and major adverse cardiovascular events (MACE) compared with patients without MetS (P < .001). Analyses of individual MetS components showed that dysglycemia at the time of DES implantation predicted increased all-cause mortality, while the presence of hypertension and dysglycemia predicted increased incidence of MACE.

Impact of transradial coronary procedures on radial artery.

OBJECTIVE: We evaluated the impact of transradial coronary procedures on the radial artery (RA). METHODS: A total of 355 patients who underwent the transradial coronary procedures including transradial coronary angiography (CAG) and percutaneous coronary intervention (PCI) were enrolled. The right RA (RRA) was examined by ultrasound. RESULTS: The mean RRA diameter was 2.37 +/- 0.57, 1.95 +/- 0.50, and 2.23 +/- 0.41 mm, respectively, before the procedure, 1 day, and 1 month after the procedures (P < .01 at 1 day, P < .05 at 1 month). The mean intima-media thickness of RRA was 0.25 +/- 0.12, 0.69 +/- 0.31, and 0.38 +/- 0.17 mm, respectively, before the procedure, 1 day and 1 month after the procedure (P < .01 at 1 day, P < .05 at 1 month). The incidence of RRA stenosis was 0%, 15.7%, and 7.6%, respectively; the incidence of RRA occlusion was 0%, 2.8%, and 1.7%, respectively, before the procedure,1 day and 1 month after the procedure. CONCLUSIONS: Transradial coronary procedures can lead to early RA injury, but this repairs later.